On the E325 screen (Found a swap file...), the user can choose
different keys to press (e.g. [O]pen Read-Only, (E)dit anyway,...). If
<Esc> is pressed, vim freezes and the terminal session has to be killed.

The same happens in other prompts, e.g. when using ctags, do ":tj
<identifier>" on an ambiguous tag (i.e. an identifier that is defined
in multiple places, like :tj main), so vim shows you all the places
where the tag is defined. You are prompted to choose which one to
open. Press <Esc> - vim freezes.